open(LOG, ">>$dir/$log_file") or croak "Unable to append to error log: $!";

##</code><code>##

    $0 =~ '(.*[\\\/])\w+\.\w+$'; 
    $dir = $1;

##</code><code>##

  $dir = $1 if $0 =~ m#/.*[\\/])\w+\.\w+$#;

##</code><code>##

use File::Basename;
$dir = dirname($0);